Your lawn may feel the heat as summer sets in, but don’t worry: Turf is tough. With some wise care, most lawns will soon rebound to their green glory. Here are some reminders for keeping lawns healthy through July and August.
Know Your GrassPerennial turfgrasses are either cool-season or warm-season. Cool-season grasses – like fescue, Kentucky bluegrass and ryegrass – grow more vigorously in cooler months. Warm-season grasses – like bermudagrass and zoysiagrass – grow most during hotter months.
Knowing what kind of grass or grasses are in your lawn will help you know how to deal with the summer heat. Tall fescue lawns tend to be more heat tolerant than Kentucky bluegrass and red fescue, which take the heat better than perennial ryegrass.
So, if you don’t know already, find out what grasses are in your lawn. Knowing what you have growing will help you properly mow and water, if needed, this summer. Your local garden center or university extension office can help with plant identification. The Center for Turfgrass Management, at Penn State University, provides video descriptions of many major turfgrass species at its website: http://plantscience.psu.edu/research/centers/turf/extension/plant-id/grasses
Water WiseOne-inch to 1.5 inches of rain per week will sustain most turfgrasses in most zones. Heat and humidity can also affect the amount of water needed. So if it doesn’t rain, should you water the yard? For lawns recently seeded, the answer is probably yes; newer seedings are still developing root systems that will get the grass through future summers. Most guidelines advise watering deeply (1 to 1.5 inches) twice weekly.
If you water: Water in the morning to avoid a wet lawn overnight, which can promote disease. And early morning watering helps water soak into the sod before the day heats up.
Bear the Brown?Watering may not be necessary, even during mild droughts; cool-season grasses will go dormant during periods of excess heat. Leaves will brown but the roots are likely still healthy, and the grass will usually green with fall rains and moderating temperatures. Tall fescue is known for being drought tolerant in this way; many Kentucky bluegrass varieties may brown during summer droughts of up to one month, then recover when rains begin.
That’s right – instead of watering the yard to keep it green all summer, consider letting nature run its course. Natural browning can even help control some yard pests, like grubs, in some areas.
Cut It HighAnd finally: Raise that mower deck. No matter how much the heat, the rule of thumb for turf health is to cut off no more than one-third the height of the grass. Ideal cutting heights vary according to variety, but many turfgrassses are healthiest when cut two to four inches.
Cutting a typical tall fescue yard higher during summer heat, say 3 to 3.5 inches, might even reduce the amount of summer mowing needed. Just be ready to return to more regular mowing when rains and cooler temperatures come, because proper summer care will help your yard return to all its green glory this fall.